An IVIS Spectrum imaging system will be purchased for use in a shared small animal imaging facility at the Albert Einstein College of Medicine. The IVIS imaging systems allow the real time imaging of small animals expressing luciferase or imaging of animals injected with cells or microbes expressing luciferase. The luciferase d-luciferin substrate is readily permeable into cells and tissue, resulting in bioluminescence imaging (BLI) of individualized organs and correlation to anatomic location. The Spectrum can image fluorescence as well (GFP, mCherry etc) in real time. The IVIS Spectrum will be used to monitor tumor or cellular migration and to monitor dissemination of a variety of pathogens. Because the luciferase or fluorescence activity can be monitored without sacrificing animals, longitudinal measurements can be made on individual mice over time. In addition 3 dimensional images can be acquired providing information about anatomic localization of reporters. The signal is proportional to cell number and can be readily quantified using the software provided with the IVIS machinery. The imaging technique will assist investigators interested in cancer biology, immunology and infectious diseases. Finally, the purchase of this instrument will enable investigators to minimize the number of animals required for their studies, as multiple images will be acquired for each animal in a study. Public Health Relevance: The Albert Einstein College of Medicine proposes to buy an IVIS Spectrum imaging instrument for a shared small animal imaging facility. This instrument will enable investigators to monitor cells expressing bioluminescent molecules or fluorescent molecules within small animals. Scientists will use this technique to understand how cancer cells metastasize, how infectious agents cause disease, how stem cells repopulate organs, and how mammals mount an immune response to pathogens or cancer.